This invention relates to a data processing system of the kind comprising a plurality of data processing elements connected together in an array such that each element can transfer data to its nearest neighbours. Such a system is described for example in British Patent Specifications Nos. 1445714, 1536933, 2020457 and 2019620.
An important consideration in the design of data processing systems is that of maintaining availability in the event of failure of a part of the system. One known method of doing this is to provide a stand-by unit which can be automatically switched-in to replace any failed unit. However, such a technique is difficult to apply in the case of a processing system of the kind referred to above, since a large number of switching circuits would be necessary to enable a stand-by processing element to be switched-in to replace any one of the processing elements.
The object of the present invention is therefore to provide a way of avoiding this difficulty.